In order to improve immersion with a wider field of view, existing flexible display devices have been implemented in such a way to employ a fixed curved display structure which has a curved screen whose screen is fixed or a variable flexible screen which is bent or unbent; or a structure with a protection unit and a driving unit for varying the radius R of the flexible display screen.
As such, conventional flexible display devices have been manufactured to be fixed in screen-size or curved screen angle or to allow a particular portion of the screen to be bent or unbent. The conventional flexible display devices, however, are not designed to maximize an advantage of flexibility.
To resolve this problem, a rollable display device having a flexible screen display has been developed. A flexible screen display can be rolled up into a scroll which is small in size or unrolled to a large screen, thereby providing the display with various screen ratios.
Since devices with a rollable display (rollable display devices) can display a screen in various sizes to meet a user's needs or optimize display of specific types of content, they are becoming more popular.
However, when rollable display devices are implemented to have a relatively large size, they need to provide higher quality display and have high endurance and safety characteristics.